Arming plants against drought

36 degrees in the shade, little rain for weeks. The maize is not growing, grains are ripening too early. How can plants survive ever-lengthier periods of heat and drought unscathed? This very issue will be examined by a new Bavarian research association involving the University of Würzburg.

"Forplanta: plants fit for the future" is the name of the new Bavarian research association which will commence its work in August 2010. The University of Würzburg's representative will be plant scientist Professor Rainer Hedrich. Joining him will be researchers from three Munich institutes of higher education and the University of Erlangen-Nuremberg. The Science Ministry will provide the association with funding of around EUR 1.5 million over the next three years.

Climate change: scientists are anticipating increasingly volatile weather conditions, with more frequent periods of drought and heat. For plants, this means water shortage and stress. As a result, they are becoming more susceptible to diseases and pests - a trend that is threatening agricultural yields.

Studying plant response to stress

How exactly do maize & co. respond to stress? "To date, only the effect of individual stress factors on plant productivity has been examined," says Rainer Hedrich. The focus of the new research association will therefore be on the responses that plants exhibit when several stress factors occur at the same time: heat, drought, and pest infestation.

The scientists are aiming to gain new insights using the model plant popular among geneticists Arabidopsis thaliana. There are species of this plant that flourish in dry and hot climes, but also in cold regions. Which genes are responsible for these adjustments? How are they controlled? Can they be manipulated to make plants less vulnerable to drought and heat? Such questions will be considered by the new research association.

Stress hormone abscisic acid at the heart of the matter

At the heart of the matter lie the water balance of plants and the hormone abscisic acid. When a water shortage occurs, this acts as a stress hormone: it prompts stomata in the outer skin of the leaves to close, with the result that the plant loses less water.

The researchers want to improve the effectiveness of this abscisic acid, so plants demonstrate satisfactory growth even when there is little water available to them. If this works: how will this manipulation affect heat tolerance and the plant's interaction with harmful fungi and bacteria? The association also intends to answer this question.

Ethical questions about green genetic engineering

The approach rooted in natural science will be accompanied by projects from the field of social science and ethics: the relationship between man and nature is also to be examined - particularly in view of green genetic engineering, i.e. the genetic modification of plants. The Forplanta association will explore this issue through the Institute for Scientific Issues related to Philosophy and Theology at the Munich School of Philosophy.

Application of knowledge to cultivated plants

If the research is successful, the intention later is to apply the findings to cultivated plants.

However, in many areas of the world, the climate is changing at a rate quicker than the speed at which plant cultivation can deliver grains adapted to stress. "Green genetic engineering should close this gap," says Professor Hedrich. "But even with this targeted and therefore faster optimization there is no time to lose. This is because it is also important that we make useful plants and crops fit to fight the pests that climate change will bring."